


SMUTFIC: Midsummer Night's Fun | Collab with Motif

by Motif, TacitlyLeaps



Series: EXPLICIT: Tacit's Lewds, Undertale [3]
Category: Undertale (Video Game)
Genre: Adopted Sibling Incest, Anal Sex, Collar, Comfy-to-Lewd, Demon Asriel, Frottage, God of Absolute Hyperdeath, Liquorice, M/M, Master/Pet, Not good for the SOUL, Oral Sex, Riding, Smut, Sweat, Tongue Fetish, Write Drunk Edit Sober, musk
Language: English
Status: Completed
Published: 2016-01-09
Updated: 2016-01-09
Packaged: 2018-05-12 20:49:10
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 7,172
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5680297
Author URL: https://archiveofourown.org/users/Motif/pseuds/Motif, https://archiveofourown.org/users/TacitlyLeaps/pseuds/TacitlyLeaps
Summary: <blockquote class="userstuff">
              <p>The now-adult Frisk and Asriel have trouble sleeping on a swelteringly hot summer night. Amidst idle cuddles and chitchat Frisk says something that Asriel uses as an excuse to get triggered and shift into his edgy and disturbingly lecherous God of Hyperdeath alter ego. </p>
<p>But this time, Frisk finds a way to turn the tables. Frisk uses his newly-found ability to get a few questions out of Asriel that he's been wondering about for years.</p>
<p>This work is a collab with the all-powerful Motif of Reprise/Coda/Cover fame! Working with him is a lot of fun and he turns everything he touches into pure gold. </p>
<p>As always, give the tags a long, hard look before delving deeper.</p>
<p>You have been warned.</p>
            </blockquote>





	SMUTFIC: Midsummer Night's Fun | Collab with Motif

**Author's Note:**

> Originally published on /utg/ - Undertale General via Pastebin.  
> Shares continuity with Good Clean Fun and Summer Sauna Fun.  
> Big thanks to the fellow writeanons on /utg/ irc who proofread and gave feedback.  
> Cherish the Motif. CHERISH!

“Oh, c'mon Az. I didn’t mean it like that.” Frisk rolled his eyes while Asriel huffed and grumbled next to him, feigning offence. It was a hot, humid summer night. The two of them were laying on top of the bed, having long since given up sleeping. Even after tossing the blankets to the side, it was just too hot to even consider it. Instead, Frisk and Asriel had just been cuddling it out and talking about nothing. Well, until Frisk had accidentally said something that had irked Asriel.

Asriel was on his back, arms folded over his chest, staring up at the ceiling with a slight frown. Frisk groaned and cuddled up next to his fluffy goat brother, draping an arm over his belly while burying his face in all that luxuriously soft neck fur, not minding it being damp and somewhat musky from sweat in the slightest. “I'm sorry, alright?” Frisk murmured with a smirk as he nuzzled his way up Asriel's neck, one of the goat's fuzzy ears flopping over the human's head.

Asriel murred quietly in a grumpy tone which Frisk, with his years of experience in interpreting goat monster, instantly recognised to be exaggerated. Frisk sighed, patting Asriel's belly before rubbing it affectionately, fingers disappearing under all that warm fur. He planted little kisses down along his monster brother's neck in an attempt to placate him, wafting warm breath over the skin hidden under the minky fur.

“Don’t think you can just apologize and smooch your way out of this. I'm not gonna let you off that easily.” Asriel spoke in a whisper, Frisk noticing a sly grin spreading on his muzzle. A moment later Frisk shivered as he felt the telltale presence of magic welling up in the air, like a brewing thunderstorm, color starting to drain from Asriel's eyes as they turned monochrome. Frisk flushed red, not really having expected Asriel to use the mildly offensive comment earlier as an excuse to go Hyperdeath. Especially considering that both of their parents were at home, sleeping a few rooms down the hallway. Asgore might snore loudly enough to keep the entire house awake some nights, but Asriel could get a lot louder when Hyperdeath’d. This boded poorly.

“Seriously, Azzy, I'm sorry.” Frisk tried to keep his voice even as he watched symmetric markings wind across his brother's body. Thanks to the swelteringly hot night, the both of them were in their boxers, and Frisk could see nearly all of the changes happening right before his eyes. The strange, tattoo-like markings creept like vines, Asriel’s cute and caring eyes becoming pools of blackness with glowing white slits in the middle, his claws staining black like obsidian and growing sharper, curving. Asriel's muscles looked more defined, and he usually added an inch or two to his height, just to appear more intimidating to Frisk.

And, well... as Frisk had personally experienced on many occasions, height wasn't the only thing Asriel added inches to.

Frisk did his best not to panic. Next on the hyperdeath to-do list was his signature laugh, which would rattle the rafters and doubtlessly wake their parents, dooming them both. Time was running out. Asriel's smirk turned into a leering and lustful grin, his lips parting slowly, prompting Frisk to act on instinct.

In a blur, Frisk grabbed Asriel's jaws, one hand cupping his chin while the other covered his snout, clamping his maw shut with a snap. Rivulets of sweat were rolling down the human's forehead as he panted lightly, staring intently at Asriel to see if his gambit would work. Asriel could channel frightening amounts of strength using his magic, which made Frisk doubt that he could actually hold his jaws shut for more than a couple seconds. His heart was racing, adrenaline flooding his system at the mere thought of their parents waking up and seeing Asriel like this, not to mention the two of them witnessing him a foot and a half inside of Frisk.

The seconds lingered for an eternity as Frisk waited for Asriel to overpower his hold and wake the whole house. But... Asriel wasn’t fighting back.

Frisk blinked, cocking his head in befuddlement. All Asriel was doing was blushing and stare at him around his hands with wide, shocked eyes. Frisk hadn't ever seen him blush or look shocked while in his edgy demonic persona. Asriel almost looked...vulnerable.

“Huh. You don't look like a god of much at the moment...” Frisk thought out loud, climbing up to sit on Asriel's belly, his hands still firmly holding the goat’s chin and snout. As Frisk moved about, he noticed that his palm rubbing against Asriel's snout made the demonic caprine squirm ever so slightly. That was unusual, not to mention cute.

Frisk squinted as he stared at Asriel's deepening blush and helpless, dewey eyes. He rubbed his smooth-skinned hand against his goatbrother's snout once more, which resulted in more weak squirming.

Frisk decided to experiment, curiosity outweighing potential risk. The hand holding Asriel's chin moved away while the other hand remained cupping his snout. He gently stroked his palm over it, a weak growl rising from the demonic goat's throat despite his flushed, embarrassed expression. Frisk added a bit more force to the rubbing, which made Asriel squirm more intently, wriggling cutely under the almost nude human.

“Wow. This is really dumb.” Frisk grinned to himself, his panic having been entirely replaced with relief and curiosity. He petted Asriel's snoot, gritting his teeth in an effort to keep himself from snickering like an idiot as the all powerful God of Hyperdeath, his tormentor, fidgeted and blushed like newborn kitten, whatever words of protest Asriel was trying to muster coming out as soft gasps and quiet bleats.

Frisk had to withdraw his hands to cover his own mouth, choking backa fit of laughter, tears beading in the corners of his eyes from how ridiculous this was. Asriel was stunned, clearly fighting off some kind of a sensory overload. Just when the demonic goat looked like he was about to recover, Frisk simply booped his snoot with a finger, Asriel flinching and shaking his head, slightly crosseyed.

“S-stop touching my sno-!” Asriel managed to cry out before another snootleboop turned the rest of his words into a cute bleat. He tried to protect his weak spot with his hands, but Frisk casually swatted them away, all strength seemingly gone from the fluffy goat's muscles.

“Ha! I knew it! You had to have a weakness.” Frisk taunted, wearing his smuggest shit eating grin while poking Asriel's nose over and over again, keeping the demonic goat stunned. When he tired of that, Frisk switched back to just affectionately stroking his palm against Asriel's snootle, giggling as he watched Asriel's glowing pupils dilate, the narrow slits becoming broad saucers. Frisk kept going until his goatbrother looked decidedly dopey.

Frisk withdrew his hand, wiggling his hips as he straightened up so that he could properly admire his handiwork. Asriel was blushing deeply, maw agape and trying to weakly close, lower jaw always faltering at the last second and dropping. His eyes were wide open, the normally slit-like pupils round like an overstimulated cat's. Frisk had no earthly clue why such a silly thing had this effect, but he wasn't going to look a gift goatgod in the mouth.

“Brother, do you realize how exploitable this is?” Frisk mumbled with a sudden air of seriousness, leaning over and looking deep into Asriel's dilated eyes while cradling his blushing cheeks. He mushed them together lightly, the soft and slightly slick fur feeling amazingly hot against the skin of his palms. Somehow, Asriel's fur felt even softer and fluffier in his Hyperdeath form, even if it didn't look any different externally.

“I could do whatever I want with yoooou.” Frisk said in a singsong voice, grinning coyly. Despite his condition, Asriel seemed to still be aware of things. He tried to mumble something, but his speech was slurred and too quiet to make out. “Yeah, how's it feel, to be completely at the whims of your brother?” Frisk teased, patting Asriel's cheeks again before letting go of them, straightening up as he looked the tattooed goat over. Truth be told, he wasn't feeling particularly frisky, despite the opportunity. It was still hot, and late, after all. He was curious about nuances of Asriel's demon-esque form, though.

That, and Asriel seemed kinda catatonic now that Frisk had stopped tormenting him for a moment.

Now that the threat of loud, lewd, demonic goat fucking had passed, Frisk decided to take his time and get a few answers to some of the things he'd always wondered about Asriel’s alternate form. Frisk placed his fingers on one of the many black markings on Asriel's body, easing the digits into the fur to ruffle it. He had suspected that the markings were just black fur, but that didn’t seem to be the case. No matter how much Frisk tried to distort the dark lines by messing up the fur, they remained as even and uniform as ever. It was like some kind of a weird magical projection – like a shadow cast over Asriel's pelt as if there was some ethereal projector and Asriel was the canvas, and yet, it didn't cover Frisk's fingers when he tried to move them through his brother's fur.

He repeated the experiment with the black markings on Asriel’s face. What a shame, it turned out that it wasn’t eyeliner. Frisk could have teased Asriel about that.

Frisk hummed thoughtfully, briefly pressing a pair of fingers against Asriel's snout to give it a nice little rub. It would be a shame for him to recover and spoil Frisk’s fun. Frisk gently cupped Asriel's chin, spreading his jaws a bit more open so that he could actually look his gift goatgod in the mouth. His teeth looked sharper than normal, and his tongue had turned black, along with his saliva. Frisk sniffed the air, shuddering as a faint tang of liquorice presented itself, causing the human to slowly close Asriel's maw. The sight of Asriel’s tongue and the scent of that corruption caused him to blush and shiver, memories of previous encounters flashing through his mind. Frisk shifted on the spot, uncomfortable with the sudden tent in his boxers. Oh god, he was starting to get conditioned by this weirdness.

Frisk felt Asriel shift about under him, rousing him from his thoughts and causing him to instinctively clench his legs together, giving Asriel's sides a squeeze. Asriel had started to come back around, waking from his little nap caused by sensory overload. Frisk was reminded of a computer recovering from a crash as Asriel lazily opened one eye, then the other, each looking in a slightly different direction, his maw opening and closing weakly.

“Hey, are you awake enough to talk? I got some questions to ask.” Frisk inquired, placing his hands on Asriel's chest, idly caressing his fine pecs as his brother awoke from the stupor. Asriel nodded after a moment’s hesitation, his movements slow and lethargic. It seemed like his muscles were nearly paralyzed, as though it took a large amount of effort to move at all.

“Y… yuh.” Asriel finally managed, Frisk raising an eyebrow with a healthy amount of doubt. This was worse than when Asriel was drunk, and the goat could drink with the best of them. Nevertheless, Frisk chose to shoot a question or two at Asriel. What was the worst that could happen?. Asriel always was very hesitant to talk about his other form while normal, and there was some kind of a state-dependent memory thing going on with his alter ego, especially when it came to trying to recall how to undo the spells he had cast while in Hyperdeath mode. Like, say, for the sake of example, turning Frisk into a goat.

Frisk’s mind wandered back to the incident at the family cabin. Asriel had gotten a little… carried away. Long story short, Frisk had ended up being turned into a Boss Monster, similar to the Dreemurrs. Now that had made for some awkward explaining, when Asgore and Toriel had come to the cabin and found Frisk fluffy and horned. Asriel had performed the change while in his Hyperdeath form, and once he had changed back, the knowledge of undoing the change had left along with his demonic powers. Frisk had managed to explain it as a “surprise”, an example of Asriel’s growing magical prodigency and a gift for the Dreemurrs’, to have a family of Monsters for a short while. It had helped that while in that form, Frisk had been able to cast magic of his own, a revelation startling enough that hardly any comments had been made about the collar Frisk had been “gifted” by Asriel during their lewd pursuits. Asgore had bought it, Frisk was pretty sure, but Toriel had been giving him sidelong glances every now and then ever since. The magic eventually wore off on its own, and even a magically enhanced collar was no match for enchanted tinsnips and Determination.

 

Frisk shook the memory off, bringing his hand away from his throat. Whenever he thought about that week, he ended up unconsciously touching his throat, as though it felt naked. Frisk wasn’t sure how to feel about that, either. Instead, he focused on the now. “Why does this happen?” Frisk asked, hands massaging their way from Asriel's chest to his shoulders, kneading the fine muscles hidden under all that luxurious fur. “The whole Hyperdeath thing, I mean. The first time with the all the Souls, and the desire to consume the timeline, that I understand. But why now?”

Asriel stayed motionless for a good few moments. Then he mustered a shrug and a weak “I’unno.”

Frisk blinked, staring at Asriel blankly. Well, that was anticlimactic. Frisk sighed, sliding his hands under Asriel's head, cradling it softly and lifting it up from the pillow. He looked at Asriel with a warm smile, fingers affectionately rubbing the back of the demonic goat's head. “If you can't talk, that's fine.”

“Nnh, no, no… I do wanna. Talk.” Asriel reassured, straining to string together a coherent sentence in peculiar stupor. “Just… Gimme a moment… What was the question…?”

“Why do you go Hyperdeath?”

“Oh.” Asriel started, a thoughtful rumble coming from his slowly heaving chest. “To make you feel good, Frisk. To help you forget.”

Frisk sat back slightly, surprised. “...Huh?”

“I'm serious, Frisk. You're the one... who's always in control. Worrying abou… everyone. Even after you saved us all.” Asriel blinked slowly, his speech flowing faster as he got into the rhythm of it. “You don't let anyone see, but... it wears you down, I can feel it. You gotta relax, sometimes, Frisk.”

Frisk sat back on his legs slightly, arms reaching up to hug at himself reflexively.

“Even when we’re snuggling… I can always feel a hint of desperation, fear, disbelief in there. Like, at any time I might just… melt. And the dread never goes away, no matter how tight I hug you back.”

Frisk glanced to the side, eyes a bit misty. He hadn't expected an answer like this, not at all.

“It’s like you’re afraid that you’re gonna wake up.”

Frisk felt a lump in his throat. His fingers clutched tufts of Asriel's fluffy fur, squeezing firmly.

Asriel suddenly sprung up, Frisk gasping as the demonic caprine took him into a loving embrace, his furry muzzle draped over Frisk's shoulders. Frisk's breath hitched, tears trickling down each cheek as his hot-furred brother held on tightly. Frisk felt Asriel's heartbeat, his claws gently pricking his bare skin, his furry cheek affectionately nuzzling against the side of his neck. A deep, reassuring murr rumbled from Asriel's chest, Frisk feeling it reverberate deep in his own body.

“This is real, Frisk. It's never gonna change. I'm always gonna be here for you.” Asriel crooned, tightening the already very snug hug. “You saved me, Frisk. So, this is my way of helping you… I know it's a little... weird. But…” Asriel chuckled a bit, Frisk furrowing his brow a little as he felt a familiar buzz of magic in his head. Asriel was poking around in there. “Pretty much everything I do, I pull from here. I just want to make you happy, Frisk. I just… want to help you forget everything, at least for a night. Give you the chance to not worry about everything, not to feel the burden of control. And I think me going, hee, 'Hyperdeath', it helps with that. Makes it feel more real for you. I mean… Can you imagine regular old me, taking charge of you like that? After everything you've overcome?”

Frisk smiled, burying his face into the side of his brother's neck. He sniffled a little, feeling… Well, touched, even if Asriel's method of helping Frisk was kinda twisted. Then again… Asriel acting twisted wasn’t completely unprecedented, if his life as a flower was counted in. But this was nice, and it apparently came from a caring place. Asriel was a caring soul, through and through.

“I know it's really messed up when you think about it. But… You always enjoy it, don't you? Even if it's massively masochistic at times. I’ve never seen anyone enjoy being bossed around so much.” Asriel rumbled, loosening the hug enough to lean back and plant a little kiss on Frisk's forehead. “And whenever we're doing our thing, it feels real, doesn't it? That buzzing dread you’re always holding onto, it’s gone, even if only for a few hours.”

“I… Th-thanks, Azzy.” Frisk mumbled, blushing but smiling. He hadn't honestly expected reasoning like that. It seemed that not everything about Asriel was immediately apparent.

Frisk tucked his head under Asriel's, closing his eyes as he nuzzled into his neck. It had a habit a long time ago, one which Frisk would never get rid of. Asriel continued to rumble soothingly, holding his human brother in a loving embrace.

A few minutes passed like that, the two brothers sharing a snug and warm hug despite the sweltering heat. Just the two of them in a loving embrace in the dead of the night, atop a comfy bed, faint sounds of nocturnal wildlife carrying through the window. A truly serene moment, Frisk thought.

“Oh, and I gotta cum to switch back to normal.”

“God damn it Azzy.”

Frisk let out an exasperated groan and peeled back from Asriel, staring at him with a stern look and a huff. “Why'd you have to ruin the moment?”

“I'm being serious. I really gotta blow some steam off to lose critical mass, so I can de-power. Like… a steam engine, I guess?” Asriel explained with a sheepish grin, trailing a solitary claw down along Frisk's spine, making the human arch his back and shiver ever so slightly.

“I swear, You're just making things up, you perv.” Frisk stated with a slight smirk, patting Asriel's other cheek for the decent effort. “Oh! While I’m thinking of it, you never said. How does the Hyperdeath thing actually work? Didn't you need a whole bunch of human and monster Souls for this?”

Asriel shrugged dismissively, Frisk noticing a familiar, lecherous glint returning to those black-and-white eyes. It was frustrating, that he’d recover enough to be coy, but his presence wasn't as intense as usual, which assuaged Frisk's worries somewhat. Hopefully things wouldn't get loud.

“Well, can't we just talk for a while, and then try sleeping again?” Frisk suggested, placing his hands on Asriel's shoulders and gently pushing him back down against the bed. He suspected the answer would be ‘No’. “We really had something special going here.”

“Afterwards. Now, let's see...” Asriel chuckled, crossing his arms under the pillow his head was resting on. A lewd grin spread on his furry muzzle as he briefly read Frisk's mind, a soft shiver going down Frisk's spine thanks to the peculiar buzzing sound it made in his head. Frisk grimaced, putting up a bit off a fight by trying to fill his thoughts with whatever random things came to mind, to act as chaff, trying to obfuscate whatever hidden desires Asriel was trying to extract from the depths of his mind.

“Golly! You're such a tease, playing hard to get like that.” Asriel murmured while probing Frisk's mind, genuinely surprised at how well the human could resist his powerful magic. “But, if you’re really not in the mood for me to pry, I guess I can let you get away with defying me, just this once. I’ll leave it up to you!” 

Asriel relaxed back onto the pillow, looking smug, and the buzzing in Frisk’s head faded away. Frisk shook his head and chuckled quietly, relieved that for once, things wouldn’t be going too far off the rails. He looked down at his brother and mused on the predicament he was faced with. Asriel in his Hyperdeath form, but compliant and passive, and needing to cum before they could sleep. Frisk wiggled his hips experimentally, inching away from Asriel's belly to sit on his thighs instead, his average boxer bulge lightly pressing against Asriel's hefty one. The bulge made by Asriel's sheath alone was nearly enough to dwarf Frisk's half-hard chub.

“You better be telling the truth about this.” Frisk mumbled as he started to slowly rub his boxers-clad groin against Asriel's, a healthy blush of arousal spreading on his cheeks as his half-hard shaft throbbed against his brother's hot and heavy bulge. “Just... stay there and don't start anything weird, okay?”

Asriel sighed softly, a lazy murr rising from his throat as he lay back and enjoyed Frisk’s ministrations. “Fine. I suppose it’s important to spoil your pets from time to time. You are free to worship your God as you please.” The demonic caprine spoke with a regal, dismissive tone, fidgeting a bit as he got more comfortable on the bed, arms still folded under his pillow. He didn't even grace Frisk with his gaze, smirking smugly as he just relaxed and waited for Frisk to do all the work.

Frisk cleared his throat, trying to ignore Asriel’s casual usage of the word ‘pet’. The naked skin on his neck pricked again, and he did his best to ignore it. Instead, Frisk kept pressing and nudging his tented boxers against Asriel's growing bulge, leaning over with a quiet moan as he found himself really getting into it. He placed his hands on Asriel's soft-furred chest for support, feeling over his fine pecs while grinding their hips together. While Frisk's boxer briefs plainly tented, Asriel's struggled to contain his swelling manhood, straining as that ten-inch slab of meat throbbed, quickly reaching its full size. A dark and sticky blotch appeared on the very tip of the goat's bulge. As per usual, Asriel was incredibly productive in his demonic form. Frisk quietly wondered how much of that was informed by how hot he found it, even as he admired how powerfully Asriel's shaft pulsed against his own through the stretched-thin fabric of their underwear, an erotic tingle traveling throughout Frisk's slender body.

The potent and arousing scent of musk filled the air as Frisk continued to grind against his caprine brother's massive bulge, a hushed groan slipping from the human's lips as he firmly pressed himself against that heated throbbing. Asriel's boxers were growing sticky from all the pre and sweat he was dripping, some of the moisture seeping into Frisk's underwear, the sensation of it making Frisk bite his lower lip, toes curling and twitching.

It took a surprising amount of willpower for him to pause long enough to finally slip a pair of fingers under Asriel's briefs and peel them down, fingers getting slick in the process, the musk in the air growing a stronger as all that damp crotchfur was exposed. The potent, exhilarating aroma hit Frisk like a hammer, the human letting out a halting gasp as the musk forced his loins to stir harder, a messy squirt of pre surging out and making a slight mess in his own underwear before he had the time to tug them down. Frisk was already struggling to maintain his composure, fingers twitching as he slid his underwear off and eventually wriggled free of them, leaving his slender, silky-skinned form fully exposed.

Frisk formulated a simple plan of action. He had to get his brother off without making a gigantic mess that they'd have to spend all night cleaning. His cheeks glowed like embers as he trailed a few fingers along Asriel's thick shaft, feeling it twitch and pulse hotly under his touch. He'd use his hands to bring the demonic goat to the edge, then let him finish inside Frisk to avoid making a mess. The idea of having Asriel inside of him made Frisk shiver with anticipation. After that, he’d find a way to keep himself from spilling his seed everywhere, and get his own rocks off, nice and clean. Maybe Asriel would let him use his maw for that…?

First things first, though. Frisk got to work. One hand remained on Asriel's chest, to keep him from slipping down on top him, while the other moved to his groin, Frisk hunching over his brother as he teasingly ground his much smaller shaft against the underside of Asriel's massive, girthy beast. His soft fingers slid over both of their manhoods in a brisk pace, trying to find all the right moments to squeeze them together, not even able to completely wrap his slender digits around Asriel's thickness, much less so with his own meager size added to it. Still, it seemed like Asriel was getting just as much pleasure from the act as he was, the tattooed goat letting out the occasional, lustful huff, bucking his hips up at Frisk’s hands at random. A heavy drool of pre-fluids leaked from the slowly throbbing goatdick, providing more than enough lubrication for the passionate grinding. In a matter of moments, Frisk's hand was completely covered with the clear and warm fluid, as was his own member, Asriel's runny pre getting everywhere on both of their crotches and thighs. Frisk hoped that none of it would end up on the sheets themselves, placing faith in Asriel's fluffy, absorbent fur.

The Prince of all Monsters languished, idly gazing up at the rafters while his human brother was busy stifling his moans, working on both of their cocks. He had a light blush on his cheeks, letting loose the occasional pleasured huff and lustful growl but otherwise contributing very little to Frisk's task, clawed fingers massaging the pillow between his neck and crossed arms.

Frisk had hoped that this would only take a couple of minutes, but the act ended up lasting a quarter hour, Frisk losing himself in the lewd, perverse act. It felt so amazing to grind his eagerly twitching shaft against his demonic brother's rock-hard and strongly pulsing manhood, his own spurts of pre completely drowned out by the sheer volume of the caprine’s constantly drooling equivalent. It was so hot and wet, there was so much of it. Frisk had always been enamoured of the sheer volume of it, the spreading, seeping, lewd slickness it heralded. Even the thought of it was enough to make him shudder. The heavy lubrication made even the smallest motion result in a wet sound, the dark bedroom now thick with the heady smell of male arousal and the gentle, slimy sounds of glistening flesh against glistening flesh.

Frisk snapped out of his trance when he felt Asriel's dick flex in a telltale fashion, the furry sac Frisk's own orbs were resting against shifting as his brother approached his peak. He managed to pull his fingers and hips away just in time to prevent Asriel from cumming, the demonic goat shuddering and stifling a guttural groan, claws almost tearing into the pillow under his head. Frisk could sense the burning lust and need rapidly welling up inside his brother, the human forced to act fast to keep the powerful monster pacified and appeased. With a determined grunt, Frisk lifted his hips up, crawling a bit further up on Asriel. He straightened his back, sitting upright on his knees, his plump rump looming over Asriel's hard and twitching shaft. Frisk trembled as he felt a few energetic spurts of goat pre splatter onto his skin.

Frisk took a moment to line himself up perfectly, looking down at Asriel with a smirk as he firmly sat down on his pre-coated cock, gritting his teeth to muffle an otherwise loud moan as he easily took in the first couple inches of his brother's shaft. It finally broke the demonic goat's languid posture, Asriel forced to briefly clamp his maw shut with both hands to keep himself from groaning out in bliss, legs kicking some and strong shudders coursing through his entire frame as Frisk slowly descended onto his dick.

“Sh-shit, Frisk...” Asriel groaned quietly, arms shivering some as he grabbed Frisk's hips, the God of Hyperdeath admitting to being delightfully surprised, something which he did rarely. It made Frisk grin triumphantly, able to keep his composure through sheer determination as he ground his hips down, shivers traveling along his spine as he worked that massive cock in to the hilt. It was a tight and extremely snug fit, stretching Frisk's normal, unaltered body to the limit, inner muscles rippling and spasming heavily around the turgid dick.

Frisk giggled as he felt his brother's shaft pulse and throb fiercely, deep inside of him, obviously teetering on the verge of orgasm. The feeling of hot pre squirting and splattering along his inner walls made Frisk squirm, his own rock-hard shaft drooling pre onto his brother’s crotch-fur. Instead of riding his caprine brother, Frisk decided to indulge in a little revenge, thinking about all those times Asriel had teased and tormented him. He gently wiggled his hips, staying more or less in place, teasing Asriel by clenching and shifting his shaft inside of him without allowing him to thrust. Beyond the fact that his brother’s tormented expression was priceless, Frisk figured that bouncing on his beloved goatbrother’s shaft would result in Frisk groaning loud enough to wake their parents up, which would be a terrible shame after having come this far.

Asriel grunted and groaned, squirming some under Frisk, throwing his head from side to side on the pillow as his hips instinctively bucked and ground up against those tantalizing hips that refused to budge. His claws pricked Frisk's silky, glistening skin, paws sliding from the human's hips to grope those round and supple asscheeks. “Ah! J-just let me finish already!” Asriel snapped, the desperation in his voice amusing Frisk to no end. The tables had finally turned.

“Beg for it.” Frisk cooed with a singsong voice, enjoying a power trip of his own, refusing to lift his hips up even a little bit. Asriel wasn't going to have any of that, Frisk feeling invisible magic build up, an almost furious frown on the demonic goat's muzzle as he was about to have his way with Frisk. Before he could, though, Frisk bent over and kissed him right on the snout, breaking the monster's concentration. A second later Frisk pulled him into a proper kiss, closing his eyes as he pressed his lips against Asriel's, hands grabbing his horns to keep him locked in the passionate smooch.

Frisk lifted his supple hips up with tormenting slowness, only leaving the tip of Asriel's furiously throbbing cock inside his tight hole before slamming his hips back down with a loud and lewd squelch. The feeling of his achingly hard dick burrowing back inside that amazingly tight ass just the one time was more than enough to make Asriel cum, the caprine moaning deeply into the kiss as gush after gush of thick goat cum pumped into his human brother. Frisk joined his brother's moaning, shuddering as a pleasureful fullness spread around his abdomen, belly rounding out gradually from the demonic goat's massive load.

Both of them eagerly held the kiss, groaning into one another’s mouths as Asriel's heavy climax continued, Asriel wriggling his tongue into Frisk's mouth, the human shuddering in perverse delight as the thick appendage pinned his own tongue under it. Frisk was rapidly slipping into a masochistic groove as Asriel teased the opening of his throat with that perversely long tongue, a soft gasp escaping him as it finally slunk into his esophagus, tickling Frisk's creepily depraved mind in all the right spots to make his eyes roll back. Waves of erotic tingles rolled over Frisk's body as that meaty goat tongue wriggled in his throat and as his insides were stuffed full of his brother's essence. Frisk's thoughts were slowing down as his mind was sinking to constant depravity, faintly registering the telltale buzz and droning of Asriel's strange mind-reading magic exploring his emotions, desires, memories… Frisk had let his guard down, and was half-fearful, half-excited at what weird, degenerate acts Asriel would soon enact upon him…

Asriel simply broke the kiss, tongue slowly reeling back and out of Frisk's mouth, the human coughing and gagging a little as he tried to cope with all the excessive and mixed drool. Even in his slightly hazy state, Frisk noted that he wasn't tasting the usual taint of liquorice, which Asriel's corrupting fluids carried. Frisk slowly opened his eyes, taking a few moments for his vision to sharpen and focus on Asriel.

Asriel was looking at him with a warm, loving smile, which would have been more fitting onhis normal form. He no longer was reading Frisk's mind, his hands affectionately caressing the rather sweaty and flushed human's sides, the goat humming a soothing tune. Frisk looked back at him with a blank expression which gradually turned into a content smile, wiping a stray streak of drool off his chin with his arm. Asriel gave him a little kiss on the chin afterwards, earning a relaxed chuckle from Frisk. Things weren't going to get any weirder tonight.

“So nervous, just because I slipped past your guard. I said you were free to do as you pleased, Frisk. Nothing without your request. Still, there’s one thing to do, though.” Asriel whispered, a pair of fingers trailing from Frisk's rumpcheek, over his hips and to the underside of his slightly pudgy belly, tracing along the side of the human's still hard and slick cock. Frisk hadn't blown his load yet, but was dangerously close to doing so, Asriel's digits sliding away at the very last possible second to avoid triggering his climax.

Frisk wasn’t sure if he should be relieved or disappointed. After all, the objective was to not make a mess, but… Asriel raised an eyebrow. “Do I detect disappointment? Was there something that you wanted me to find?”

There it was. Frisk looked away, burning with embarrassment. Asriel chuckled, running a finger along Frisk’s chest. “I’m not even going to look inside you for this. If you want something, you’re going to have to ask for it.”

Damn it. Damn him. Frisk clenched his fists, hunching over, gritting his teeth as the gigantic cock inside of him pressed against all the right spots, his own cock twitching with need, right on the edge, his body screaming at him to just say it already. Fine.

“I… This is… It’s missing something.”

Asriel waited. Frisk hated that it worked.

“Can you… you know.” Frisk fidgeted on the spot, trying to force the words out. “Can you make… Another… Collar?”

Asriel’s grin widened, showing teeth, his eyes narrowing. He reached up with both hands, gently caressing the bare skin on Frisk’s neck, and the touch tingled. Frisk gasped as something seemed to grow out from the points he caressed, wrapping his throat in a familiar and comforting tightness. It felt… so right.

Friek reached up with a hand, touching it. It even had the red heart tag, which clinked softly to the touch.

“You barely did anything.”

“It was already there, in your mind. After all, this is yours, where it belongs.” Asriel’s expression softened a little. “Besides, like I said, it looks cute on you.”

Frisk didn’t even have the willpower to hit him, stewing in the wash of sensations assaulting him, one hand gently playing with the tight leather against his skin.

Asriel gestured Frisk to get up, sticking the tip of his tongue out, it taking a moment for Frisk to realize what he was after. It never even occurred to Frisk not to do as he was bid. Frisk sat up from his brother's lap, that huge and still rather hard shaft sliding out of his hole, a small amount of still hot cum managing to escape before the puckered entrance closed up properly. Frisk crawled to kneel over Asriel's head, his furry muzzle between his tastefully thick thighs, the goat chuckling a little at Frisk’s sudden willingness. Frisk gasped as he felt his snout nuzzle his orbs, gently nudging them for a few seconds before his maw tilted up, Frisk's cheeks flushing bright red as he felt Asriel's lips seal around the tip of his shaft with a soft smack.

Frisk's fingers clutched tufts of Asriel's headfur, then his horns, as the goat swallowed more of his feverishly twitching shaft with tormenting slowness. The humid, slimy heat around his sensitive flesh made Frisk's dick sputter with pre, the pudgy-bellied human gasping and outright whimpering as that royal maw sucked his manhood in. Feeling Asriel drag his tongue along the underside of his cock made Frisk arch his back, toes curling and fingers twitching. This was actually the first time that Asriel had used his maw in his demonic form to suck Frisk off, and it had been worth the wait.

Frisk couldn't hold back his orgasm by the time Asriel's lips first made contact with his groin, biting his tongue and clenching his eyes shut as he muffled a moan of ecstasy as he started to cum. He could feel his pulse against the collar around his neck. Streaks of pearly white spunk shot into Asriel's maw, the goat chuckling coyly as he allowed his brother's load to pool on his tongue before swallowing with a loud gulp. Asriel softly suckled on Frisk's shaft, draining every last drop of seed that he could from the human, dutifully gulping it down to keep the mess outside of their bodies to a minimum.

Frisk's load was pitiful compared to Asriel's stomach-swelling release, only managing a little over half dozen squirts before it tapered off to a slow dribble. Asriel made sure to lick and suck his brother's member clean before pulling his head back, planting a kiss on Frisk's nuts before looking up at him with a tired smile. Frisk was panting, dripping with sweat thanks to the heat from the lewd acts and the summer night, an equally exhausted smile on his features. It took him plenty of effort to get up, crawl down over Asriel and just slump down on him, nuzzling into sweaty neckfur as the strange demonic markings began to disappearing, reeling back into nothingness as Asriel returned to normal.

“I think… I'm gonna sleep, now.” Frisk murmured with a tired giggle, wrapping his arms under Asriel's neck as he rested on the musky and damp goat, Asriel chuckling and sighing relief and pleasure. His clawed paws hugged around Frisk, gently holding onto him as they both drifted into deep sleep.

***

Asriel and Frisk began to stir in unison as the loud sounds of a lawnmower carried to their ears. Judging by the amount of light piercing through both the blinds and the curtains it was about noon. They were usually both heavy sleepers after a night of Hyperdeath.

Asriel yawned, smacking his jaws a few times while Frisk lazily rolled off of his goatbrother. The funky taste in his mouth and musty smell burning in his nose motivated Frisk to get off the bed and groggily stumble over to the window, cracking it open to let some fresh air in. He only now noticed how thick with the musk of sex and sweat was, Frisk clearing his throat and sniffing loudly to eject the dank air out of his lungs and nose.

Frisk idly scratched his belly while returning to the bed, noticing that it had shrunk back almost to normal. He had no idea if he had an amazingly effective digestive system, or if monster cum had the same qualities as monster food. In either case, he was glad that he wouldn't have to explain any sudden thickness to his folks. Frisk sat down on the edge of the bed, immediately getting back up because of how damp with sweat everything was, a shudder going down his spine.

It felt like there was a thin film of filth clinging to his skin. Frisk supposed that was true, considering he'd been sweating all night, and snuggling with an equally sweaty goat. And that was before they had fucked. “Hey Az, wanna go take shower with me?” Frisk inquired, already moving to the closet to dig up a pair of towels.

Asriel yawned loudly, still laying on the bed, on his back. With visible effort, he sat up and hoisted his legs over the bed, scratching his gut and neck for a few moments before standing up and stretching out. “Shur. One thing, though.” The Prince of Monsters mumbled while blinking sleep out of his eyes, his fluffy fur matted with sweat and ruffled all around. Not to mention the particularly nasty-looking knots in his more private region, courtesy of his excessive pre last night.

Frisk caught Asriel unprepared as he tossed a rolled up towel at him, the groggy and still rather tired goat fumbling and managing to drop it on the floor. That earned an amused snerk from Frisk, the ruffled caprine groaning as he had to lean down to pick it up. Frisk swooped in for the rescue, deftly grabbing the towel from the floor and handing it back to Asriel, giggling and using the excuse to steal a little kiss off Asriel's lips. It made the groggy goat blush and rumble, returning the favor by nosing with Frisk briefly, one hand creeping up Frisk’s chest and causing something to jangle with a small metallic sound. Frisk stopped dead.

“Forget about something?”

Frisk felt the blush creeping over his cheeks all over again. He’d totally forgotten. Wearing this collar felt so natural he hadn’t even noticed it when he woke up.

“Uh, I-”

“Shh, let me.” Asriel lifted a hand and did something, and the collar fell away from Frisk’s neck. Asriel handed it to him, and Frisk stared down at it dumbly. It had a silver buckle, this time.

“I think you should put it somewhere safe, seeing how you like it so much. Now come on, I need a shower.”


End file.
